s390x/tcg: flush the tlb on SIGP SET PREFIX

Thanks to Aurelien Jarno for doing this in his prototype.

We can flush the whole TLB as this should happen really rarely.
Signed-off-by: NDavid Hildenbrand <david@redhat.com>
Message-Id: <20170928203708.9376-26-david@redhat.com>
Reviewed-by: NRichard Henderson <richard.henderson@linaro.org>
Signed-off-by: NCornelia Huck <cohuck@redhat.com>

target/s390x/sigp.c

@@ -287,6 +287,7 @@ static void sigp_set_prefix(CPUState *cs, run_on_cpu_data arg)
     }
 
     cpu->env.psa = addr;
+    tlb_flush(cs);
     cpu_synchronize_post_init(cs);
     si->cc = SIGP_CC_ORDER_CODE_ACCEPTED;
 }